gate
For general aptitude and english I don't think you need to do anything extra. Just prepare simple topics like
Time and work
Profit and loss
Ratio and proportions
Percentage
Analogy
Read some idioms and phrases , maybe you are lucky and will answer them correctly. Don't worry too much about it. Just be normal and prepare normally and you will do well in this portion.
The level of questions in this section is not so high, so an average person can easily score 10 out of 15 . YOu just need to be focussed.
Do these topics for GATE exam and everything will be fine.